import numpy as np
import matplotlib.pyplot as P 
pi=3.14159;
def grid(N,length=2*pi):
  length=2*pi;
  dx=length/N
  dy=dx
  print 'dx,dy=',dx,dy
  xx=np.zeros(N)
  yy=np.zeros(N)
  for ix in range(1,N):
      xx[ix]= ix*dx
      yy[ix]= ix*dy
  return xx,yy,dx,dy
#************************************#
def pgrid(N,length=2*pi):
  xx,yy,dx,dy=grid(N,length)
  unity=np.ones(N);
  for ix in range(1,N):
     P.plot(xx,yy[ix]*unity,'k')
     P.plot(xx[ix]*unity,yy,'k')
  return xx,yy,dx,dy
#************************************#
if __name__ == '__main__':
  grid();
else:
  print 'Importing ode solver'
